Optical Coherence Tomography (OCT) systems are used to capture and generate three-dimensional images of patient tissue layers. These systems include OCT probes that often invasively penetrate tissue to obtain visualization of tissue within a patient. In ophthalmology, OCT probes are used to obtain detailed images of tissue about the eye or even forming a part of the eye, such as the retina.
In use, an optical light beam is directed through the probe at the tissue. A small portion of this light reflects from sub-surface features of the tissue and is collected through the same probe. Most light is not reflected but, rather, diffusely scatters at large angles. In conventional imaging, this diffusely scattered light contributes background that obscures an image. However, in OCT, a technique called interferometry records the optical path length of received photons, and provides data that reject most photons that scatter multiple times before detection. This results in images that are more clear and that extend in the depth of the tissue.